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Unexpected benzimidazole ring formation from a quinoneimide species in the presence of ammonium acetate as supporting electrolyte used in the coupling of electrochemistry with mass spectrometry 下载免费PDF全文
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Wen Chen Olivier Maurel Christian La Borderie Thierry Reess Antoine De Ferron Mohammed Matallah Gilles Pijaudier-Cabot Antoine Jacques Frank Rey-Bethbeder 《Heat and Mass Transfer》2014,50(5):673-684
The objective of this study is to simulate the propagation of the shock wave in water due to an explosion. The study is part of a global research program on the development of an alternative stimulation technique to conventional hydraulic fracturing in tight gas reservoirs aimed at inducing a distributed state of microcracking of rocks instead of localized fracture. We consider the possibility of increasing the permeability of rocks with dynamic blasts. The blast is a shock wave generated in water by pulsed arc electrohydraulic discharges. The amplitude of these shock waves is prescribed by the electrohydraulic discharges which generate high pressures of several kilobars within microseconds. A simplified method has been used to simulate the injected electrical energy as augmentation of enthalpy in water locally. The finite element code EUROPLEXUS is used to perform fluid fast dynamic computation. The predicted pressure is consistent with the experimental results. In addition, shock wave propagation characteristics predicted with simulation can be valuable reference for design of underwater structural elements and engineering of underwater explosion. 相似文献
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Alibe Ibrahim Mustapha Matori Khamirul Amin Sidek Hj Ab Aziz Yaakob Yazid Rashid Umer Alibe Ali Mustapha Zaid Mohd Hafiz Mohd Nasir Salisu Nasir Maharaz Mohammed 《Journal of Thermal Analysis and Calorimetry》2019,136(6):2249-2268
Journal of Thermal Analysis and Calorimetry - Willemite is an inorganic semiconductor material used for optoelectronic applications. The present study purposes a new polymer thermal treatment... 相似文献
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Novel and sensitive UPLC–MS/MS method for quantification of sofosbuvir in human plasma: application to a bioequivalence study 下载免费PDF全文
Mamdouh R. Rezk Emad B. Basalious Mohammed E. Amin 《Biomedical chromatography : BMC》2016,30(9):1354-1362
A novel and sensitive LC–MS/MS method was developed and validated for determination of sofosbuvir (SF) using eplerenone as an internal standard. The Xevo TQD LC–MS/MS was operated under the multiple‐reaction monitoring mode using electrospray ionization. Extraction with tert‐butyl methyl ether was used in sample preparation. The prepared samples were chromatographed on Acquity UPLC BEH C18 (50 × 2.1 mm, 1.7 μm) column by pumping 0.1% formic acid and acetonitrile in an isocratic mode at a flow rate of 0.35 mL/min. Method validation was performed as per the US Food and Drug Administration guidelines and the standard curves were found to be linear in the range of 0.25–3500 ng/mL for SF. The intra‐ and inter‐day precision and accuracy results were within the acceptable limits. A very short run time of 1 min made it possible to analyze more than 500 human plasma samples per day. A very low quantification limit of SF allowed the applicability of the developed method for determination of SF in a bioequivalence study in human volunteers. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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